Sung Taehyun, Seong Sicheon, Han Seulki, Son Young Ji, Ishida Tomoya, Hayashi Tomohiro, Hara Masahiko, Noh Jaegeun
J Nanosci Nanotechnol. 2018 Oct 1;18(10):7053-7057. doi: 10.1166/jnn.2018.15501.
Displacement processes of pre-covered cyclohexanethiol (CHT) self-assembled monolayers (SAMs) by 4-fluorobenzenethiol (4-FBT) on Au(111) were examined as a function of displacement time by scanning tunneling microscopy (STM) and water static contact angle (CA) measurements. STM imaging revealed that the adsorption of 4-FBT on Au(111) in a 1 mM ethanol solution at room temperature for 24 h generated disordered SAMs, whereas well-ordered 4-FBT SAMs with a (4√6 × √3)R5° packing structure were formed over the entire Au(111) surfaces via the displacement of pre-covered CHT SAMs by 4-FBT molecules. The CA measurements also showed that CA values increase with increasing displacement time, reflecting that the displacement reaction took place and the resulting SAMs had greater hydrophobicity compared with CHT SAMs. In this study, we found that the displacement technique using CHT SAMs as a molecular template is very useful in obtaining 4-FBT SAMs with a high degree of structural order and large ordered domains.
通过扫描隧道显微镜（STM）和水静态接触角（CA）测量，研究了在Au(111)上4-氟苯硫酚（4-FBT）对预覆盖环己硫醇（CHT）自组装单分子层（SAMs）的置换过程与置换时间的关系。STM成像显示，室温下在1 mM乙醇溶液中，4-FBT在Au(111)上吸附24小时会产生无序的SAMs，而通过4-FBT分子置换预覆盖的CHT SAMs，在整个Au(111)表面形成了具有(4√6 × √3)R5°堆积结构的有序4-FBT SAMs。CA测量还表明，CA值随置换时间的增加而增大，这反映出置换反应发生，且与CHT SAMs相比，所得SAMs具有更大的疏水性。在本研究中，我们发现以CHT SAMs作为分子模板的置换技术对于获得具有高度结构有序性和大的有序域的4-FBT SAMs非常有用。
